The present invention disclosed herein relates to semiconductor devices, and more particularly, to semiconductor devices having a resistor.
A flash memory device, which is a type of nonvolatile memory device, may be classified into a floating gate type and a charge trap type according to a kind of a data storage layer of a unit cell. A MONOS (metal/oxide/nitride/oxide/silicon) flash memory device, which is a charge trap type flash memory device, includes a cell transistor of which a gate structure is configured with a tunneling insulating layer, a charge storage layer, a blocking insulating layer, and a metal gate electrode.
The MONOS flash memory device includes a passive element, such as resistor, as well as an active element, such as a transistor. The resistor used in a reference circuit or the like in a conventional MONOS flash memory device typically has a small area, and the resistor is typically fabricated using polysilicon with high resistance, which may be insensitive to process variations. Thus, to reduce fabrication cost and increase productivity, it may be desirable to form the resistor at the same time when other elements are formed in a semiconductor device.